REALISM is a prospective, multi-center, study of the safety and effectiveness of an endovascular approach to the treatment of mitral valve regurgitation using the Evalve Cardiovascular Valve Repair System (MitraClip® implant). Patients with moderate-to-severe (3+) or severe (4+) mitral regurgitation (MR), as determined by the site from a transthoracic echocardiogram (TTE), were considered for enrollment in this study. The TTE and a transesophageal echocardiogram (TEE) are used to assess eligibility criteria for MR severity, valve anatomy and left ventricular parameters.